Biomedical Engineering Reference
In-Depth Information
TABLE 3.2 NMs with Medical Applications
NMs
Drug/application
Reference
Polybutyl(cyanoacrylate)
Dalargin/analgesic
Kreuter et al.
241
Polybutyl(cyanoacrylate)
Doxorubicin/antitumor
Gelperina et al.
242
Dextran-coated iron oxide
NMs
Ferridex/MRI contrast
agent
Sakamoto et al.
243
Carboxydextran-coated
iron oxide NMs
Resovist/ MRI contrast
agent
Sakamoto et al.
243
Singh et al.
244
Polymersomes
Paclitaxel/drug delivery
CdSe/ZnS.
150,196,240
The QDs were nonimmunogenic, stable, and when coated with
an organic layer allowed for an array of proteins, DNA, and other biomolecules to
be conjugated to their 60 surfaces. Because of their small size and surface modifi-
cation, the QDs were conjugated with vaccine candidates against malaria.
192
These
NMs not only served as a delivery platform for protein antigens, but also activated
key immune cells to further increase the immunogenicity of the vaccine. Their in
vivo tests demonstrated no immediate toxic effects but QDs that contain Cd are not
compatible for human use. However, the toxicity of the CdSe/ZnS QDs was limited
by coating the core with a shell layer of ZnS that is further coated with an amphiphi-
lic polymer. Because of the possibility of eventual polymer and NMs degradation,
attempts are currently being made to develop cadmium-free QD NMs as well as the
use of other NMs that do not contain Cd such as IOMNPs, AuNPs, etc.
Most biosensors reported in the literature use electrochemical transduc-
tion. This is due to the low cost, high sensitivity, ease of miniaturization, low
power requirements, and simple fabrication of electrochemical transducers.
245
Electrode materials are often made up of carbon, gold, platinum, or conducting
polymers. Nanostructured electrode materials are gaining importance in elec-
trochemical transduction since their greater surface area allows incorporation of
more biorecognition elements thereby enabling lower detection limits and faster
response times. NMs have unique optical, electrical, magnetic, and catalytic
properties that facilitate label-free detection of target analytes.
CNTs have been increasingly used as substrates in electrochemical sensors
due to their size and interesting physical and chemical properties. CNTs as sub-
strates for amperometric sensors can be grown via microwave plasma vapor
deposition using dendrimer-templated Fe NMs as catalyst.
246
CNT arrays have
been grown via chemical vapor deposition on platinum. Multiwalled carbon
nanotubes (MWNTs) have been deposited on glassy carbon electrode using
the layer-by-layer technique with polyaniline as the oppositely charged poly-
electrolyte.
247
CNT in a vertically aligned “forest” configuration can be grown
